As a society and nation we are increasingly aware of the value of preventive medicine. In the area of hearing health, prevention is achieved by awareness of elements hazardous to hearing and the early diagnosis of small changes in hearing status. The current diagnostic protocol used in audiology has been in place for over half a century and is insensitive to small changes in auditory physiology. We propose to evaluate novel methods of detecting alterations in hearing status. These novel methods are implemented within a test-battery that should effectively evaluate several aspects of hearing function and relate to communication difficulties experienced by individuals in the real world. Work during the first phase of the project evaluates the effectiveness of a new diagnostic system currently under development in our labs and examines the efficacy of methods of calibration, as well as recording of stimulus frequency otoacoustic emissions. This system will integrate the administration of all tests proposed here and be able to administer them over an unprecedented range of frequencies. The results of this phase are incorporated into a second phase where a battery of tests is evaluated in an age-distributed group of 400 subjects. In the final and largest phase of the study, we glean the most effective tests from the previous phase and evaluate their efficacy in a battery, as well as individually, on a sample of 1200 subjects. This phase is conducted over the last three years of the project period, at three sites. Two of the proposed study sites are functional audiology clinics in university and medical environments, respectively. Consistent with the translational goals of the project we develop a new measurement device which incorporates new methods of evaluating the auditory system. We evaluate these tests in a large cohort of diverse subjects. Finally, we engage in aggressive, evidence-based promotion of these new technologies and methods, as suggested by the overall findings of our study. [unreadable] [unreadable] [unreadable] [unreadable]